Cleaning



Patented June 7, 1949 UNITED STATES ATENT OFFICE LOOSENING CO MPOSITION Charles A. Jensen, Buffalo, N. Y.

No Drawing. Application September 6, 1945, Serial No. 614,815

1 Claim.

This invention relates to a cleaning, penetrating and corrosion loosening composition and more particularly to such a composition in liquid form for weakening the bond between metallic surfaces formed by the products of corrosion and for cleaning and removing corrosion from corroded metallic surfaces. It has also been 'found that the composition is unusually effective in cleaning enameled or painted surfaces, particularly in cleaning the bodies of automobiles.

One of the principal objects of the invention is to provide a composition which will penetrate throughout the area between two metallic surfaces bonded by corrosion and which will attack and loosen the corrosive cement joining the surfaces.

Another object of the invention is to facilitate the removal of the products of corrosion from metallic surfaces.

Another object is to provide such a composition which is stable and which will not injure or discolor the hands of the person using the same.

Another object is to provide such a composition which is low in cost.

Another object is to provide such a compound which can be safely used as a cleaner for automobile bodies and the like and which leaves the cleaned surface free from streaks, stains or other blemishes.

Other objects and advantages will appear from the following description.

Compositions known to the art as penetrating oils are in common use to aid in the separation of corroded metallic parts. Insofar as it is known their action is due solely to the penetrating and lubricating qualities of the oils employed. Compositions of this nature are usually composed of low viscosity oils to aid in penetration and of a heavier bodied oil to provide for lubrication. Other agents may be added to accentuate either of these properties.

Although such penetrating oils may lessen the force required to move corroded parts in relation to each other they do not, apparently, alter the composition of the corrosive cement joining the surfaces and so fail to weaken the chemical bonds joining these surfaces. Badly corroded metallic parts are therefore frequently not materially affected by the application of such penetrating oils and hence must be separated by mechanical and often expensive processes.

I have discovered that the above objects of the present invention can be attained by the use of an oil of normal composition, or other relatively inert non-aqueous liquid carrier, containing in solution or in the form of an emulsion a compound of the formula RX, in which R is either an organic or inorganic element or radical and X is one of the first three members of the halogen group, that is, fluorine, chlorine or bromine. I have further discovered that the nature of the group or element represented by the symbol R is unimportant if (1) the resulting compound enters readily into the reaction (2) the compound is either soluble in non-aqueous and relatively inert solvents or capable of forming low viscosity emulsions with non-aqueous and relatively inert liquids, and (3) the resulting composition is stable in the absence of water.

In connection with the above formula RX as used in the accompanying claim, R is designated as an element which is intended to include one or more atoms of a single element or a combination or radical, either organic or inorganic, of atoms of different elements.

Examples of such compounds are: stannic chloride, aluminum chloride, titanium tetrachloride, silicon tetrachloride, phosphorous pentachloride, phosphorous oxychloride, phosphorous trichloride, carboxylic acid chlorides, chlorinated acid chlorides, chlorinated acid anhydrides, chlorinated acid ketones, chlorinated acid esters, thionyl chloride, sulfuryl chloride, and the corresponding fluorine and bromine derivatives. This list is not intended to be complete and examples of other types of compounds fulfilling the above qualifications, will occur to those familiar with the art.

Such compounds are dissolved or emulsified in a non-aqueous relatively inert liquid, such as mineral oil, to provide the penetrating and corrosion loosening composition embodying the present invention. The choice of the solvent or liquid in which the compound is emulsified is not limited, however, to petroleum hydrocarbons. Other solvents, both synthetic and of animal or vegetable origin, can be used with similar eifect provided that they are relatively inert and either immiscible or only slightly miscible with water.

The preferred concentration is such that the composition shall contain an amount of halogen compound, equivalent to 0.3-1.0 gram-atoms of halogen, per liter of solution. However, lower or higher concentrations can be used without critically impairing the corrosion loosening properties of the composition. In appreciably higher concentrations, however, the composition tends to absorb moisture from the air and to form an acid which is itself severely corro v and wh ch may cause significant injury to the metal parts on which it is used. The preferred composition embodying this invention consists of a solution formed by dissolving 20 milliliters of phosphorous trichloride in one liter of an oil equivalent in viscosity to that composed of 25% of a low viscosity lubricating oil and 75% of an intermediate-boiling petroleum fraction, such as kerosene.

The composition forming the subject of the present invention has been found to be effective in loosening and removing the corrosion on iron, aluminum, magnesium, and zinc surfaces as well as their alloys.

It could not be predicted that a halide belonging to the above class would, when dissolved or emulsified in an oil, confer onthe oil improved penetrating and corrosion loosening properties. It is well known that these compounds, when dissolved in water, form the corresponding hydrogen halide which helps to remove corrosion products. by conferring water solubility on them.

However, there is nothing, to my knowledge, in the prior art which would indicate that these compounds in a. non-aqueous medium and in the small concentrations used-would be in any way effective in loosening or removing corrosion.

It is believed that the action of these compounds is due to an exchange reaction between the metallic oxide and the halide, in which oxygen is partially or wholly replaced by halogen and that this reaction is responsible for the cleavage of the bond between the metal and the surface oxide. In the absence of water, the product of the reaction may be oil soluble and may either be washed away by an excess of the oil or further take part in a chain reaction in which fresh and non-adhesive metallic oxide is redeposited. Other explanations are possible for the-action of these compounds and it is not intended that the scope of this invention shall in any way be limited by the explanation offered.

In a typical example of the use of the composition forming the subject of the present invention, the steel nuts holding the aluminum cylinder head of an engine to the engine block could not be loosened by the maximum force, short of breakage, which could be applied. The nuts were then coated with the composition forming the subject of the present invention and permitted to stand 15 hours. After this treatment the nuts, without exception, were easily removed.

In another example of the use of the composition forming the subject of the present invention, a steel ball-and-socket joint, corroded by ten years of exposure to the elements and fumes of a chemical plant, was coated with the composition after the usual mechanical methods had been tried in a vain effort to separate the ball from the socket. After standing a few hours the joint was readily and quickly taken apart. As an example of the corrosion removing qualities of the composition forming the subject of the present invention two identical pieces of sheet iron, uniformly coated with rust, were treated, the one with a standard penetrating oil and the other with the composition forming the subject of the present invention. After two hours both pieces of sheet iron were rubbed with a dry cloth. The piece of sheet iron treated with the standard penetrating oil retained a coating of rust and only the top layer of rust was removed. The piece of sheet iron treated with the composition forming the subject of the presentinvention lost almost completely its rust coating and a bright metal surface was obtained.

In another example of the use of the composition forming the subject of the present invention, the composition was applied, by means of a cloth, to the soiled body of an automobile. With very little rubbing the body was left in a clean condition free from streaks, marks, stains or other blemishes. This was then followed by the application of wax.

The composition forming the subject of the present invention, as above described, was found to effectively loosen or remove corrosion from the surface of magnesium, aluminum, zinc and iron, and their alloys. It proved to be only slightly eifective on cadmium, nickel, chromium and lead, and without effect on copper.

From the foregoing it will be seen that the present invention provides a low cost liquid composition which is not dangerous and can readily be applied to metal enameled parts and when so applied has high cleaning penetrating and corrosion loosening properties so as to enable corroded parts to be readily freed from each other or to remove the surface corrosion on such parts.

I claim as my invention:

A cleansing, penetrating and corrosion loosening composition consisting essentially of phosphorus trichloride and a liquid petroleum hydrocarbon consisting essentially of lubricating oil and kerosene in the approximate proportions of 25% of lubricating oil and'75% of kerosene, said phosphorus trichloride and liquid petroleum hydrocarbon being in the approximate proportion of 0.3 to 1.0 gram-atoms of chlorine to one liter of the composition.

CHARLES A. JENSEN.

REFERENCES CITED The following references are of record in the OTHER REFERENCES Chemical Formulary, vol. 1, page 363. 

